[FFmpeg-trac] #764(avcodec:new): Increasing robustness of runlength decoding for scantable access in mpeg12.c

[FFmpeg]

#764: Increasing robustness of runlength decoding for scantable access in
mpeg12.c
-------------------------------------+-------------------------------------
             Reporter:  erik         |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avcodec
              Version:  unspecified  |               Resolution:
             Keywords:  mpeg         |               Blocked By:
  robustness                         |  Reproduced by developer:  0
             Blocking:               |
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------

Comment (by erik):

 The ac-tex check is missing in
 mpeg1_fast_decode_block_inter
 mpeg2_fast_decode_block_non_intra

 When I put

 {{{
  if (i < 0 || i >= 64 ) av_log(s->avctx, AV_LOG_ERROR,  "scantable error,
 i = %d\n", i);
 }}}
 just before the scan table access I get many of these error messages
 example:
 [mpeg2video @ 003d69c0] scantable error, i = 330

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/764#comment:12>
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